That's not a hang - there's a script running that consumes a lot of cpu (searchhi.js), which tries to highlight the search words that you used on Google. But after 10 seconds, the warning dialog comes up, and you can stop it.

Note that it never hanged for me, I'm not sure why nizamov.shawkat@gmail.com experienced that.
With Mozilla 4.0.1, there's no slow-script warning either. Either the activestate.com changed something in their script, or Firefox 4.0 is now faster, and doesn't complain anymore. I guess the former.
nizamov.shawkat@gmail.com : it's it ok for you to close this bug ? Do you still see the problem ?

Yes, I still observe erratic behaviour with Firefox 4.0.1, on 2 PC's on both Windows XP 32-bit and Ubuntu 64-bit. On both systems after opening the redirection URL (from Comment #1, step 4, not from the original bugreport!) firefox shows up a part of activestate page, then it freezes for a few seconds, then it become responsive for a few seconds again and then freezes forever. Monitoring system resource I noticed that it uses 100% CPU and steadily grows up in memory till several gigabytes. On Linux then it would be killed by OOM-killer. On Windows it shows a window with message like "Firefox crashed, send a bug report back to Mozilla?". I answered "Yes", so another bugreport should be registered somewhere on Mozilla's servers. After then Firefox restarts, restores windows and guess what - it still hangs on both systems! I do not know why others can not reproduce it while I can on both computers that are available for me right now. Just followed the link from Comment#1.

Here it is:
https://crash-stats.mozilla.com/report/index/bp-902d8f4b-5dd3-4cea-961d-3974b2110531
Hungs were occuring with 3.6.4, now I am using 4.0.1.
On Linux it really hungs, but gets silently killed by OS. On Windows it now generates a crash report.
My environment is quite generic, the only thing that I could suspect is that we have to use a squid based proxy to access internet. Unfortunately, I can not check the case without proxy. Anyway I hardly believe that this could cause such problems.

That crash signature doesn't contain any useful information. Any other crash id's listed?
On Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.17) Gecko/20110420 Firefox/3.6.17 ID:20110420140830 I get the slow running script dialog after ~10 seconds.
On Mozilla/5.0 (Windows NT 5.1; rv:7.0a1) Gecko/20110610 Firefox/7.0a1 ID:20110610030736 I am getting a fairly long hang (>30 seconds) and then finally get the slow running script warning:
A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.
Script: http://code.activestate.com/static/js/searchhi.js:43

Hi!
I tried to reproduce the crashes, but Firefox silently upgraded from version 4.0 to version 5.0 on both PC's that I use. Now I also observe the same behavior with Firefox 5.0 as you - after a hang for a few seconds (5-15) I see the slow running script warning, on both Linux and WinXp.
So, the bottom line is that bug was present in Firefox versions including 4.0 and have gone in Firefox 5.0. Probably, bugreport could be now closed, it is not relevant anymore.

Still getting a ~30 second hang with Mozilla/5.0 (Windows NT 5.1; rv:8.0a1) Gecko/20110723 Firefox/8.0a1 ID:20110723030814 and then get the slow running script dialog.
Same results with closing the tab, opening a new tab, and revisiting the URL.

hi @Gabriela.
I am having windows 7 and firefox version is 14.0.1
Facebook ticker problem is resolved.
but, still there is some random error.
It occurs after continuous usage for hours, I can't track the exact event when the hang occurs.

Hello,
I can not reproduce this bug anymore (FF 14 on WinXP and Linux). There is even no slow script warning, url/page is opened and rendered as fast as it could be generally expected. Probably, the bug is fixed meanwhile, however, it can be attributed to the changes in my systems too.